The Geographical Distribution of the Frankeniaceae ete. 417 
salt-steppes and along sea coasts very different in their extent and position 
than those of the present time. The present conditions point to the southern 
continents as being the area of this developement, and it may be that in 
western Australia where the two branches Toichogonia isolata and Basigonia 
meet, the former with two species, the latter with four or more, we have 
still a modern coherent portion of the developement. It is not necessary to 
suppose that all of the regions which now contain the remnants, were at 
that time connected by salt-steppes or even by coast lines, but we know 
that after the Tertiary period, the land newly reclaimed from the sea, and 
therefore presumably fit only to sustain a halophytie vegetation, would, in 
South America for example, have reached far to the north of the present 
location of the Argentine salt-steppes. It is entirely possible that species 
like F. Palmeri on the lower Californian coast, F. Vidali on the islands of San 
Felix and San Ambrosio, Beatsonia on St. Helena, owe their existence there 
to a transportation of seed from some other region, but not from the regions 
which their congeners now occupy. 
The entire absence of these isolated elements in South Africa, indeed 
from the whole of Africa, is noteworthy. Their prevalence in Australia 
and extratropical South America suggests a clo. er relation of these conti- 
nents geographically than exists at present. The distribution coincides to 
a noticable extent with that of the Old Oceanic Floral elements, and one may 
be allowed the speculation whether the nearer relation between Australia 
and South America could have occurred for the Frankeniaceae in the exis- 
tence of a more northerly reaching coast of the Antarctic continent. This 
would necessitate the supposition that a very much milder climate prevailed 
than now, in as much as the Frankeniaceae grow only in tropical or sub- 
tropical climates, and the hypothesis is even more untenable because the 
old Oceanic floral element contains no halophytic groups. 
Any further statements than the facts of distribution and of evident 
genetic relationship are necessarily hypothetical. The following propo- 
sitions are, however, offered as being to a reasonable degree supported by 
the facts of distribution and relationship: 
1. That there existed a prehistoric developement of Frankeniaceae iden- 
tified in its distribution with the then existing salt — steppe and 
coast lands, particularly of the southern continents. 
2. That the present sections Toichogonia isolata and Basigonia with the 
genera Beatsonia, Hypericopsis and Niederleinia are elements of this 
former developement, which exist as isolated remnants. 
3. That sections Eufrankenia and Toichogonia cosmopolita are an element 
originating from the earlier developement, but distinguished by their 
great capacity for multiplication and distribution. 
Botanische Jahrbücher. XXIV. Ba. 27 
